Re: [PATCH V3 1/5] perf/x86/intel/uncore: customized pmu event read for client IMC uncore

[Thomas Gleixner]

On Tue, 24 Oct 2017, kan.liang@xxxxxxxxx wrote:
> -	if (event->hw.idx >= UNCORE_PMC_IDX_FIXED)
> +	if (event->hw.idx == UNCORE_PMC_IDX_FIXED)
>  		shift = 64 - uncore_fixed_ctr_bits(box);
>  	else
>  		shift = 64 - uncore_perf_ctr_bits(box);
> diff --git a/arch/x86/events/intel/uncore_snb.c b/arch/x86/events/intel/uncore_snb.c
> index db1127c..9d5cd3f 100644
> --- a/arch/x86/events/intel/uncore_snb.c
> +++ b/arch/x86/events/intel/uncore_snb.c
> @@ -498,6 +498,30 @@ static void snb_uncore_imc_event_del(struct perf_event *event, int flags)
>  	snb_uncore_imc_event_stop(event, PERF_EF_UPDATE);
>  }
>  
> +static void snb_uncore_imc_event_read(struct perf_event *event)
> +{
> +	struct intel_uncore_box *box = uncore_event_to_box(event);
> +	u64 prev_count, new_count, delta;
> +	int shift;
> +
> +	if (event->hw.idx >= UNCORE_PMC_IDX_FIXED)

And this needs to be >= because?

> +		shift = 64 - uncore_fixed_ctr_bits(box);
> +	else
> +		shift = 64 - uncore_perf_ctr_bits(box);

Thanks,

	tglx